Dermatology Flashcards
Causes of acanthosis nigricans
type 2 diabetes mellitus
Addisons disease
gastrointestinal cancer
obesity
polycystic ovarian syndrome
acromegaly
Cushing’s disease
hypothyroidism
familial
Prader-Willi syndrome
drugs- combined oral contraceptive pill, nicotinic acid
Typical features of acne vulgaris
Comedones are due to a dilated sebaceous follicle
-if the top is closed a whitehead is seen
-if the top opens a blackhead forms
Inflammatory changes seen in acne vulgaris
papules
pustules
An excessive inflammatory response may result in:
nodules
cysts
NB- eventually scars may form eg. ice pick scars, hypertrophic scars
Management of acne vulgaris
Mild- benzoyl peroxide, topical antibiotics, and topical retinoids
Moderate- oral antibiotics, and anti-androgens (in females) eg. COCT (Dianette- risk of VTE)
Severe- oral retinoids (eg. isoretinoin)
NB- ABX of choice: tetracyclines: lymecycline, oxytetracycline, doxycycline (erythromycin in pregnancy, breastfeeding, children under 12)
NB- pregnancy is contraindicated to oral or topical retinoids
Actinic keratoses
Pre-malignant skin lesions that form as a result of chronic sun exposure;
small, crusty or scaly, lesions
may be pink, red, brown or the same colour as the skin
typically on sun-exposed areas e.g. temples of head
multiple lesions may be present
Management of actinic keratoses
Lifestyle- sun avoidance, sun cream
Medical- fluorouracil cream (sometimes topical hydrocortisone is given following fluorouracil to help settle the inflammation), topical diclofenac, topical imiquimod, cryotherapy
Surgery- curettage and cautery
BCC
Most common cancer in the Western world
many types of BCC are described. The most common type is nodular BCC, which is described here
sun-exposed sites, especially the head and neck account for the majority of lesions
initially a pearly, flesh-coloured papule with telangiectasia
may later ulcerate leaving a central ‘crater’
Management;
surgical removal
curettage
cryotherapy
topical cream: imiquimod, fluorouracil
radiotherapy
Bowens disease
Bowen’s disease is a type of precancerous dermatosis that is a precursor to squamous cell carcinoma. It is more common in elderly patients. There is around a 5-10% chance of developing invasive skin cancer if left untreated.
red, scaly patches
often 10-15 mm in size
slow-growing
often occur on sun-exposed areas such as the head (e.g. temples) and neck, lower limbs
Management of Bowens disease
-may sometimes be diagnosed and managed in primary care if clear diagnosis or repeat episode
-topical 5-fluorouracil (typically used twice daily for 4 weeks, often results in significant inflammation/erythema. Topical steroids are often given to control this)
-cryotherapy
-excision
Bullous Pemphigoid
An autoimmune condition causing sub-epidermal blistering of the skin.
itchy, tense blisters typically around flexures
the blisters usually heal without scarring
there is usually no mucosal involvement (i.e. the mouth is spared)*
investigation- immunofluorescence shows IgG and C3 at the dermoepidermal junction
Management- refer to dermatology, oral steroids and immunosuppressants, also oral steroids and ABX
Assessing extent of a burn
Lund and Browder chart: the most accurate method
Which burns are referred to secondary care
all deep dermal and full-thickness burns.
superficial dermal burns of more than 3% TBSA in adults, or more than 2% TBSA in children
superficial dermal burns involving the face, hands, feet, perineum, genitalia, or any flexure, or circumferential burns of the limbs, torso, or neck
any inhalation injury
any electrical or chemical burn injury
suspicion of non-accidental injury
Initial burn management
superficial epidermal: symptomatic relief - analgesia, emollients etc
superficial dermal: cleanse wound, leave blister intact, non-adherent dressing, avoid topical creams, review in 24 hours
severe/full thickness: IV fluids, stabilise airway, escharotomy/plastics input
Cherry haemangioma
erythematous, papular lesions
typically 1-3 mm in size
non-blanching
not found on the mucous membranes
Chronic plaque psoriasis
Chronic plaque psoriasis is the most common form of psoriasis seen in clinical practice, accounting for around 80% of presentations.
erythematous plaques covered with a silvery-white scale
typically on the extensor surfaces such as the elbows and knees. Also common on the scalp, trunk, buttocks and periumbilical area
clear delineation between normal and affected skin
plaques typically range from 1 to 10 cm in size
if the scale is removed, a red membrane with pinpoint bleeding points may be seen (Auspitz’s sign)
50% have associated nail changes (e.g. pitting, onycholysis)
Contact dermatitis
irritant contact dermatitis: common - non-allergic reaction due to weak acids or alkalis (e.g. detergents). Often seen on the hands. Erythema is typical, crusting and vesicles are rare
allergic contact dermatitis: type IV hypersensitivity reaction. Uncommon - often seen on the head following hair dyes. Presents as an acute weeping eczema which predominately affects the margins of the hairline rather than the hairy scalp itself. Topical treatment with a potent steroid is indicated
Dermatitis herpetiformis
An autoimmune blistering skin disorder associated with coeliac disease. It is caused by deposition of IgA in the dermis.
Features- itchy, vesicular skin lesions on the extensor surfaces (e.g. elbows, knees, buttocks) and abdomen
Diagnosis- skin biopsy: direct immunofluorescence shows deposition of IgA in a granular pattern in the upper dermis
Management
-gluten-free diet
-dapsone
Deramtofibroma
solitary firm papule or nodule, typically on a limb
typically around 5-10mm in size
overlying skin dimples on pinching the lesion
Eczema herpeticum
Eczema herpeticum describes a severe primary infection of the skin by herpes simplex virus 1 or 2.
It is more commonly seen in children with atopic eczema and often presents as a rapidly progressing painful rash.
On examination, monomorphic punched-out erosions (circular, depressed, ulcerated lesions) usually 1–3 mm in diameter are typically seen. May have itchy vesicles that contain pus. May have lymphadenopathy
As it is potentially life-threatening children should be admitted for IV aciclovir.
Erysipelas
Erysipelas is localised skin infection caused by Streptococcus pyogenes. In simple terms, it is a more superficial, limited version of cellulitis.
The treatment of choice is flucloxacillin.
Erythema ab igne
Erythema ab igne is a skin disorder caused by over exposure to infrared radiation. Characteristic features include reticulated, erythematous patches with hyperpigmentation and telangiectasia. A typical history would be an elderly women who always sits next to an open fire.
If the cause is not treated then patients may go on to develop squamous cell skin cancer.
Erythema multiforme
a hypersensitivity reaction which is most commonly triggered by infections. It may be divided into minor and major forms.
Causes;
viruses: herpes simplex virus (the most common cause), Orf
idiopathic
bacteria: Mycoplasma, Streptococcus
drugs: penicillin, sulphonamides, carbamazepine, allopurinol, NSAIDs, oral contraceptive pill, nevirapine
connective tissue disease e.g. Systemic lupus erythematosus
sarcoidosis
malignancy
Features of erythema multiforme
target lesions
initially seen on the back of the hands / feet before spreading to the torso
upper limbs are more commonly affected than the lower limbs
pruritus is occasionally seen and is usually mild
NB- the more severe form, erythema multiforme major is associated with mucosal involvement.
Erythema nodosum
inflammation of subcutaneous fat
typically causes tender, erythematous, nodular lesions
usually occurs over shins, may also occur elsewhere (e.g. forearms, thighs)
usually resolves within 6 weeks
lesions heal without scarring
Causes of erythema nodusum
infection
-streptococci
-tuberculosis
-brucellosis
systemic disease
-sarcoidosis (with raised calcium)
-inflammatory bowel disease
-Behcet’s
malignancy/lymphoma
drugs
-penicillins
-sulphonamides
-combined oral contraceptive pill
pregnancy
NB- IBD and sarcoid most common
Erythrasma
Erythrasma is a generally asymptomatic, flat, slightly scaly, pink or brown rash usually found in the groin or axillae. It is caused by an overgrowth of the diphtheroid Corynebacterium minutissimum
Examination with Wood’s light reveals a coral-red fluorescence.
Topical miconazole or antibacterial are usually effective. Oral erythromycin may be used for more extensive infection
Erythroderma
Erythroderma is a term used when more than 95% of the skin is involved in a rash of any kind.
Causes of erythroderma;
eczema
psoriasis
drugs e.g. gold
lymphomas, leukaemias
idiopathic
Erythrodermic psoriasis
may result from progression of chronic disease to an exfoliative phase with plaques covering most of the body. Associated with mild systemic upset
more serious form is an acute deterioration. This may be triggered by a variety of factors such as withdrawal of systemic steroids. Patients need to be admitted to hospital for management
Guttate psoriasis
Guttate psoriasis is more common in children and adolescents. It may be precipitated by a streptococcal infection 2-4 weeks prior to the lesions appearing.
Features;
tear drop papules on the trunk and limbs
gutta is Latin for drop
pink, scaly patches or plques of psoriasis
tends to be acute onset over days
Management of guttate psoriasis
most cases resolve spontaneously within 2-3 months
there is no firm evidence to support the use of antibiotics to eradicate streptococcal infection
topical agents as per psoriasis
UVB phototherapy
tonsillectomy may be necessary with recurrent episodes
Onychomycosis
fungal infection of the nails
Risk factors include for fungal nail infections include diabetes mellitus and increasing age.
Features
-‘unsightly’ nails are a common reason for presentation
-thickened, rough, opaque nails are the most common finding
Differential diagnosis;
psoriasis
repeated trauma
lichen planus
yellow nail syndrome
Investigation;
nail clippings
scrapings of the affected nail
Management of fungal nail infections
Asymptomatic and not bothered- no treatment
dermatophyte infection (Trichophyton rubrum)- oral terbinafine is currently recommended first-line with oral itraconazole as an alternative. 6 weeks - 3 months therapy is needed for fingernail infections whilst toenails should be treated for 3 - 6 months. treatment is successful in around 50-80% of people
Candida infection- mild disease should be treated with topical antifungals (e.g. Amorolfine) whilst more severe infections should be treated with oral itraconazole for a period of 12 weeks
NB- ine’s are first line, oral itraconazole second line
NB- T for T, terbinafine for trichophyton
HHT
an autosomal dominant condition characterised by (as the name suggests) multiple telangiectasia over the skin and mucous membranes. Twenty percent of cases occur spontaneously without prior family history.
epistaxis : spontaneous, recurrent nosebleeds
telangiectases: multiple at characteristic sites (lips, oral cavity, fingers, nose)
visceral lesions: for example gastrointestinal telangiectasia (with or without bleeding), pulmonary arteriovenous malformations (AVM), hepatic AVM, cerebral AVM, spinal AVM
NB- usually have a positive FH
Hidradenitis suppurativa
a chronic, painful, inflammatory skin disorder. It is characterized by the development of inflammatory nodules, pustules, sinus tracts, and scars in intertriginous areas. It should be suspected in pubertal or post-pubertal patients who have a diagnosis of recurrent furuncles or boils, especially in intertriginous areas.
Management of Hidradenitis suppurativa
Lifestyle- Encourage good hygiene and loose-fitting clothing, Smoking cessation, Weight loss in obese
Acute flares can be treated with steroids (intra-lesional or oral) or flucloxacillin. Surgical incision and drainage may be needed in some cases.
Long-term disease can be treated with topical (clindamycin) or oral (lymecycline or clindamycin and rifampicin) antibiotics.
Lumps that persist despite prolonged medical treatment are excised surgically.
Hirsutism (women)
androgen-dependent hair growth in women (ie. specific to androgenous regions ie. face, chin, axillae, pubis etc.)
Polycystic ovarian syndrome
Cushing’s syndrome
congenital adrenal hyperplasia
androgen therapy
obesity: thought to be due to insulin resistance
adrenal tumour
androgen secreting ovarian tumour
drugs: phenytoin, corticosteroids
Hypertrichosis (women and men)
androgen-independent hair growth (ie. not specific to androgenous regions ie. whole body)
drugs: minoxidil, ciclosporin, diazoxide
congenital hypertrichosis lanuginosa, congenital hypertrichosis terminalis
porphyria cutanea tarda
anorexia nervosa
Management of hirsutism
advise weight loss if overweight
combined oral contraceptive pill
facial hirsutism: topical eflornithine - contraindicated in pregnancy and breast-feeding
Hyperhidrosis
Excessive sweating
topical aluminium chloride preparations are first-line. Main side effect is skin irritation
iontophoresis: particularly useful for patients with palmar, plantar and axillary hyperhidrosis
botulinum toxin: currently licensed for axillary symptoms
surgery: e.g. Endoscopic transthoracic sympathectomy. Patients should be made aware of the risk of compensatory sweating
Impetigo
a superficial bacterial skin infection usually caused by either Staphylcoccus aureus or Streptococcus pyogenes. It can be a primary infection or a complication of an existing skin condition such as eczema, scabies or insect bites (common in children)
‘golden’, crusted skin lesions typically found around the mouth
very contagious
Management;
conservative- children should be excluded from school until the lesions are crusted and healed or 48 hours after commencing antibiotic treatment
Localised- hydrogen peroxide 1% cream, topical fuscidic acid if unable
Severe- oral flucloxacillin (erythromycin)
Keloid scars
tumour-like lesions that arise from the connective tissue of a scar and extend beyond the dimensions of the original wound
Predisposing factors;
ethnicity: more common in people with dark skin
occur more commonly in young adults, rare in the elderly
common sites (in order of decreasing frequency): sternum, shoulder, neck, face, extensor surface of limbs, trunk
Treatment;
early keloids may be treated with intra-lesional steroids e.g. triamcinolone
excision is sometimes required
Keratocathoma
Keratoacanthoma is a benign epithelial tumour. They are more common with advancing age and rare in young people.
Features - said to look like a volcano or crater
initially a smooth dome-shaped papule
rapidly grows to become a crater centrally-filled with keratin
Spontaneous regression of keratoacanthoma within 3 months is common, often resulting in a scar. Such lesions should however be urgently excised as it is difficult clinically to exclude squamous cell carcinoma. Removal also may prevent scarring.
Ketoconazole
Due to the high risk of hepatic toxicity (ranging from hepatitis to cirrhosis/liver failure) it advised against the use of oral ketoconazole completely.
This does not affect the prescription of topical ketoconazole
Koebner phenomenon
The Koebner phenomenon describes skin lesions that appear at the site of injury. It is seen in:
psoriasis
vitiligo
warts
lichen planus
Leukoplakia
a premalignant condition which presents as white, hard spots on the mucous membranes of the mouth. It is more common in smokers.
Biopsies are usually performed to exclude alternative diagnoses such as squamous cell carcinoma and regular follow-up is required to exclude malignant transformation to squamous cell carcinoma, which occurs in around 1% of patients.
Lichen planus
itchy, papular rash most common on the palms, soles, genitalia and flexor surfaces of arms
rash often polygonal in shape, with a ‘white-lines’ pattern on the surface (Wickham’s striae)
Koebner phenomenon may be seen (new skin lesions appearing at the site of trauma)
oral involvement in around 50% of patients: typically a white-lace pattern on the buccal mucosa
nails: thinning of nail plate, longitudinal ridging
Planus (P’s)- purple, pruritic, papular, polygonal rash on flexor surfaces. Wickham’s striae over surface. Oral involvement common
Lichenoid drug eruptions - causes:
-gold
-quinine
-thiazides
Management of lichen planus
topical steroids
benzylamine mouthwash or spray is recommended for oral lichen planus
extensive lichen planus- oral steroids or immunosuppression
Lichen sclerosus
an inflammatory condition that usually affects the genitalia and is more common in elderly females. Lichen sclerosus leads to atrophy of the epidermis with white plaques forming
Features;
white patches that may scar
itch is prominent
may result in pain during intercourse or urination
Management- topical steroids and emollients (biopsy if it doesn’t respond)
NB- increased risk of vulval cancer
Lipoma
Benign tumour of adipocytes
smooth
mobile
painless
Usually not treated- if diagnosis uncertain, or compressing on surrounding structures then may be removed
Liposarcoma
Very rare for lipomas to undergo malignant transformation
Features suggestive of sarcomatous change:
Size >5cm
Increasing size
Pain
Deep anatomical location
Types of melanoma
Superficial spreading- A growing mole
Nodular- Red or black lump or lump which bleeds or oozes (worst prognosis)
Lentigo maligna- A growing mole
Acral lentiginous- Subungual pigmentation (Hutchinson’s sign) or on palms or feet
Diagnostic features of melanoma
The main diagnostic features (major criteria):
-Change in size
-Change in shape
-Change in colour
Secondary features (minor criteria)
-Diameter >= 7mm
-Inflammation
-Oozing or bleeding
-Altered sensation
The ‘ABCDE Symptoms’ rule (major suspicious features):
Asymmetrical shape
Border irregularity
Colour irregularity*
Diameter > 6mm
Evolution of lesion (e.g. change in size and/or shape)*
Symptoms (e.g. bleeding, itching)
Management of melanoma
Suspicious lesions should undergo excision biopsy. The lesion should be removed in completely as incision biopsy can make subsequent histopathological assessment difficult.
Once the diagnosis is confirmed the pathology report should be reviewed to determine whether further re-excision of margins is required
Malignant melanoma prognostic factors
The invasion depth of a tumour (Breslow depth) is the single most important factor in determining prognosis of patients with malignant melanoma
Molluscum contagiosum
a common skin infection caused by molluscum contagiosum virus
Transmission occurs directly by close personal contact, or indirectly via fomites
The majority of cases occur in children
Features of molluscum contagiosum
characteristic pinkish or pearly white papules with a central umbilication, which are up to 5 mm in diameter
Lesions appear in clusters in areas anywhere on the body (except the palms of the hands and the soles of the feet).
In children, lesions are commonly seen on the trunk and in flexures, but anogenital lesions may also occur.
In adults, sexual contact may lead to lesions developing on the genitalia, pubis, thighs, and lower abdomen.
Rarely, lesions can occur on the oral mucosa and on the eyelids.
Management of molluscum contagiosum
Lifestyle- self-limiting and should resolve in 18 months, don’t scratch, contagious so don’t share towels etc.
Medical- usually not required, but may be pierced, cryotherapy, or emollient with steroid if itching
Referral for molluscum contagiosum
For people who are HIV-positive with extensive lesions urgent referral to a HIV specialist
For people with eyelid-margin or ocular lesions and associated red eye urgent referral to an ophthalmologist
Adults with anogenital lesions should be referred to genito-urinary medicine, for screening for other sexually transmitted infections
Mycosis fungoides
a rare form of T-cell lymphoma that affects the skin.
Features;
itchy, red patches which are
lesions tend to be of different colours in contrast to eczema/psoriasis where there is greater homogenicity
Mycosis fungoides
a rare form of T-cell lymphoma that affects the skin.
Features;
itchy, red patches which are
lesions tend to be of different colours in contrast to eczema/psoriasis where there is greater homogenicity
Pellagra
caused by nicotinic acid (niacin, B3) deficiency. The classical features are the 3 D’s - dermatitis (around the neck), diarrhoea and dementia.
Pellagra may occur as a consequence of isoniazid therapy (isoniazid inhibits the conversion of tryptophan to niacin) and it is more common in alcoholics.
Pemphigus vulgaris
an autoimmune disease. It is more common in the Ashkenazi Jewish population.
mucosal ulceration is common and often the presenting symptom. Oral involvement is seen in 50-70% of patients
skin blistering - flaccid, easily ruptured vesicles and bullae. Lesions are typically painful but not itchy. These may develop months after the initial mucosal symptoms. Nikolsky’s describes the spread of bullae following application of horizontal, tangential pressure to the skin
acantholysis on biopsy
Management- steroids, then immunosuppressants
Perioral dermatitis
a condition typically seen in women aged 20-45 years old. Topical corticosteroids, and to a lesser extent, inhaled corticosteroids are often implicated in the development of the condition.
Features;
clustered erythematous papules, papulovesicles and papulopustules
most commonly in the perioral region but also the perinasal and periocular region
Management;
steroids may worsen symptoms
should be treated with topical or oral antibiotics
Pityriasis rosea
an acute, self-limiting rash which tends to affect young adults. The aetiology is not fully understood but is thought that herpes hominis virus 7 (HHV-7) may play a role.
Features;
a minority may give a history of a recent viral infection
herald patch (usually on trunk)
followed by erythematous, oval, scaly patches which follow a characteristic distribution with the longitudinal diameters of the oval lesions running parallel to the line of Langer (‘fir-tree’ appearance)
NB- usually disappears after 6-12 weeks
Pityriasis (tinea) versicolour
a superficial cutaneous fungal infection caused by Malassezia furfur (formerly termed Pityrosporum ovale)
Features;
most commonly affects trunk
patches may be hypopigmented, pink or brown (hence versicolor). May be more noticeable following a suntan
scale is common
mild pruritus
Predisposing factors;
occurs in healthy individuals
immunosuppression
malnutrition
Cushing’s
Management of pityriasis versicolour
topical antifungal- ketoconazole shampoo
if failure to respond to topical treatment then consider alternative diagnoses (e.g. send scrapings to confirm the diagnosis) + oral antifungal eg. itraconazole
Polymorphic eruption of pregnancy
pruritic condition associated with the last trimester
lesions often first appear in abdominal striae
the periumbilical area is often spared
management depends on severity: emollients, mild potency topical steroids and oral steroids may be used
NB- Atopic eruption of pregnancy is the commonest skin disorder found in pregnancy
it typically presents as an eczematous, itchy red rash.
Pompholyx
a type of eczema which affects both the hands and the feet
Pompholyx eczema may be precipitated by humidity (e.g. sweating) and high temperatures.
Features;
small blisters on the palms and soles
pruritic
often intensely itchy
sometimes burning sensation
once blisters burst skin may become dry and crack
Management;
cool compresses
emollients
topical steroids
Porphyria cutanea tarda
classically presents with photosensitive rash with blistering and skin fragility on the face and dorsal aspect of hands (most common feature)
hypertrichosis
hyperpigmentation
Investigations;
urine: elevated uroporphyrinogen and pink fluorescence of urine under Wood’s lamp
serum iron ferritin level is used to guide therapy
Management;
chloroquine
venesection
Causes of pruritis
Liver disease
Post stroke priritus
Iron deficiency anaemia
Polycythaemia
CKD
Lymphoma
hyper- and hypothyroidism
diabetes
pregnancy
‘senile’ pruritus
urticaria
skin disorders: eczema, scabies, psoriasis, pityriasis rosea
Nail changes and psoriasis
pitting
onycholysis (separation of the nail from the nail bed)
subungual hyperkeratosis
loss of the nail
NB- 90% people with psoriatic arthritis have nail changes
Exacerbation of psoriasis
trauma
alcohol
drugs: beta blockers, lithium, antimalarials (chloroquine and hydroxychloroquine), NSAIDs and ACE inhibitors, infliximab
withdrawal of systemic steroids
Streptococcal infection may trigger guttate psoriasis.
Causes of purpura in children
Meningococcal septicaemia
• Acute lymphoblastic leukaemia
• Congenital bleeding disorders
• Immune thrombocytopenic purpura
• Henoch-Schonlein purpura
• Non-accidental injury
DIC
Causes of purpura in adults
• Immune thrombocytopenic purpura
• Bone marrow failure (secondary to leukaemias, myelodysplasia or bone metastases)
• Senile purpura
• Drugs (quinine, antiepileptics, antithrombotics)
• Nutritional deficiencies (vitamins B12, C and folate)
Pyoderma gangrenosum
a rare, non-infectious, inflammatory disorder. It is an uncommon cause of very painful skin ulceration. It may affect any part of the skin, but the lower legs are the most common site.
Features;
usually starts quite suddenly
small pustule, red bump or blood-blister
the skin then breaks down resulting in an ulcer which is often painful
the edge of the ulcer is often described as purple, violaceous and undermined.
the ulcer itself may be deep and necrotic
may be accompanied by systemic symptoms eg.
fever, myalgia
Causes of pyoderma gangrenosum
idiopathic in 50%
-inflammatory bowel disease in 10-15%
-ulcerative colitis
-Crohn’s
rheumatological
-rheumatoid arthritis
-SLE
haematological
-myeloproliferative disorders
-lymphoma
-myeloid leukaemias
-monoclonal gammopathy (IgA)
-granulomatosis with polyangiitis
primary biliary cirrhosis
Management of pyoderma gangrenosum
Oral steroids and possibly immunosuppressants
Surgery when disease is controlled
Pyogenic granuloma
most common sites are head/neck, upper trunk and hands. Lesions in the oral mucosa are common in pregnancy
initially small red/brown spot
rapidly progress within days to weeks forming raised, red/brown lesions which are often spherical in shape
the lesions may bleed profusely or ulcerate
Management;
-lesions associated with pregnancy often resolve spontaneously post-partum
-other lesions usually persist. Removal methods include curettage and cauterisation, cryotherapy, excision
NB- difference with pyoderma gangrenosum is that they are raised
Adverse effects of retinoids
-teratogenicity- females should ideally be using two forms of contraception (e.g. Combined oral contraceptive pill and condoms)
-dry skin, eyes and lips/mouth (most common)
-low mood/ suicidal ideation
-raised triglycerides
-hair thinning
-nose bleeds (caused by dryness of the nasal mucosa)
-intracranial hypertension (not be combined with tetracyclines)
-photosensitivity
-joint pains
Rosacea (acne rosacea)
typically affects nose, cheeks and forehead
flushing is often first symptom
telangiectasia are common
later develops into persistent erythema with papules and pustules
rhinophyma
ocular involvement: blepharitis
sunlight may exacerbate symptoms/
Lifestyle- sun cream applied every day
Medical- topical metronidazole, severe disease is treated with systemic antibiotics e.g. Oxytetracycline
Specialist- laser therapy (if prominent telangiectasia)
Scabies
caused by the mite Sarcoptes scabiei and is spread by prolonged skin contact.
Features;
widespread pruritus
linear burrows on the side of fingers, interdigital webs and flexor aspects of the wrist
in infants, the face and scalp may also be affected
secondary features are seen due to scratching: excoriation, infection
Management of scabies
Lifestyle- avoid close physical contact with others until treatment is complete, all household and close physical contacts should be treated at the same time, even if asymptomatic, iron or tumble dry clothing, bedding, towels, etc., on the first day of treatment to kill off mites.
Medical- permethrin 5% is first-line, malathion 0.5% is second-line
NB- pruritus persists for up to 4-6 weeks post eradication
NB- Ivermectin for crusted scabies
Seborrheic dermatitis in adults
a chronic dermatitis caused by an inflammatory reaction to Malassezia furfur (fungus)
Seborrheic dermatitis in adults
a chronic dermatitis caused by an inflammatory reaction to Malassezia furfur (fungus)
Features;
-eczematous lesions on the sebum-rich areas: scalp (may cause dandruff), periorbital, auricular and nasolabial folds
-otitis externa and blepharitis may develop
Associated conditions;
-HIV
-Parkinson’s disease
Management;
Scalp- over the counter preparations containing zinc pyrithione (‘Head & Shoulders’) and tar (‘Neutrogena T/Gel’), then ketoconazole
Rest of body- topical antifungals: e.g. ketoconazole and topical steroids: best used for short periods
Shingles
an acute, unilateral, painful blistering rash caused by reactivation of the varicella-zoster virus (VZV). Following primary infection with VZV (chickenpox), the virus lies dormant in the dorsal root or cranial nerve ganglia.
Features;
prodromal period;
burning pain over the affected dermatome for 2-3 days
pain may be severe and interfere with sleep
around 20% of patients will experience fever, headache, lethargy
rash;
initially erythematous, macular rash over the affected dermatome
quickly becomes vesicular
characteristically is well demarcated by the dermatome and does not cross the midline. However, some ‘bleeding’ into adjacent areas may be seen
NB- clinical diagnosis
Management of shingles
Lifestyle- tell patients they are infected, cover lesions, avoid pregnant women and immunosuppressed (wait until vesicles have crusted over, usually 5-7 days),
Medical- analgesia: paracetamol and NSAID’s (neuropathic if needed), antivirals within 72 hours of onset (aciclovir)- reduces the chance of post-herpetic neuralgia (can be given after 72 hours of they are at risk ie/ immunosuppressed/elderly)
Complications- herpes zoster opthalmicus, herpes zoster oticus (ramsay hunt), post-herpetic neuralgia
Spider naevi
Causes;
Idiopathic
liver disease
pregnancy
combined oral contraceptive pill
NB- Spider naevi fill from the centre (spiders sit in the centres of their web), telangiectasia from the edge
Risk factors for SCC
excessive exposure to sunlight / psoralen UVA therapy
actinic keratoses and Bowen’s disease
immunosuppression e.g. following renal transplant, HIV
smoking
long-standing leg ulcers (Marjolin’s ulcer)
genetic conditions e.g. xeroderma pigmentosum, oculocutaneous albinism
Management- surgical excision, radiotherapy - for large, non-resectable tumours
Steven-Johnson syndrome
a severe systemic reaction affecting the skin and mucosa that is almost always caused by a drug reaction.
Features;
-rash is typically maculopapular with target lesions being characteristic. May develop into vesicles or bullae
-mucosal involvement
-systemic symptoms: fever, arthralgia
Causes;
penicillin
sulphonamides
lamotrigine, carbamazepine, phenytoin
allopurinol
NSAIDs
oral contraceptive pill
NB- hospital admission, steroids, immunoglobulins and immunosuppressant medications guided by a specialist.
Tinea
a term given to dermatophyte fungal infections. Three main types of infection are described depending on what part of the body is infected
tinea capitis - scalp
tinea corporis - trunk, legs or arms
tinea pedis - feet
Tinea capitis (scalp ringworm)
oral antifungals: terbinafine for Trichophyton tonsurans infections and griseofulvin for Microsporum infections. Topical ketoconazole shampoo should be given for the first two weeks to reduce transmission
Tinea corporis (ringworm)
causes include Trichophyton rubrum and Trichophyton verrucosum (e.g. From contact with cattle)
well-defined annular, erythematous lesions with pustules and papules
may be treated with oral fluconazole
Tinea pedis (athlete’s foot)
characterised by itchy, peeling skin between the toes
common in adolescence
Toxic epidermal necrolysis (TEN)
a potentially life-threatening skin disorder that is most commonly seen secondary to a drug reaction. In this condition, the skin develops a scalded appearance over an extensive area. Some authors consider TEN to be the severe end of a spectrum of skin disorders which includes erythema multiforme and Stevens-Johnson syndrome
Features
-systemically unwell e.g. pyrexia, tachycardic
-positive Nikolsky’s sign: the epidermis separates with mild lateral pressure
Drugs known to induce TEN
-phenytoin
-sulphonamides
-allopurinol
-penicillins
-carbamazepine
-NSAIDs
Management of TEN
Conservative- stop precipitating factor, admit to hospital
Medical- supportive care (ICU), volume loss and electrolyte derangement are potential complications, IV immunoglobulins, immunosuppression
Urticaria
describes a local or generalised superficial swelling of the skin. The most common cause of urticaria is allergy although non-allergic causes are seen.
Features;
pale, pink raised skin. Variously described as ‘hives’, ‘wheals’, ‘nettle rash’
pruritic
Management;
non-sedating antihistamines are first-line (loratadine, cetirizine, sedating would be prochlorperazine eg.)
prednisolone is used for severe or resistant episodes
Chickenpox (primary varicella) vaccine
This is a live attenuated vaccine.
Example indications include:
-healthcare workers who are not already immune to VZV
-contacts of immunocompromised patients (e.g. child whose parent is undergoing chemotherapy)
Venous ulceration
Investigations;
-ankle-brachial pressure index (ABPI) is important in non-healing ulcers to assess for poor arterial flow which could impair healing
-a ‘normal’ ABPI may be regarded as between 0.9 - 1.2. Values below 0.9 indicate arterial disease. Interestingly, values above 1.3 may also indicate arterial disease, in the form of false-negative results secondary to arterial calcification (e.g. In diabetics)
Management;
-compression bandaging, usually four layer (only treatment shown to be of real benefit)
Vitiligo
an autoimmune condition which results in the loss of melanocytes and consequent depigmentation of the skin.
Features;
well-demarcated patches of depigmented skin
the peripheries tend to be most affected
trauma may precipitate new lesions (Koebner phenomenon)
Associated conditions;
type 1 diabetes mellitus
Addison’s disease
autoimmune thyroid disorders
pernicious anaemia
alopecia areata
Management;
lifestyle- sunblock, camouflage make-up
medical- topical corticosteroids, topical tacrolimus and phototherapy (caution needs to be exercised with light-skinned patients)
Erysipelas vs cellulitis
Erysipelas is distinguished from cellulitis by a well-defined, red raised border
Erysipelas vs cellulitis
Erysipelas is distinguished from cellulitis by a well-defined, red raised border
Risks for melanoma
excessive UV exposure, skin type I (always
burns, never tans), history of > 100 moles or atypical neavus syndrome moles, family history in first degree relative or previous history of melanoma
Features of eczema
acute- bitchy papules with exudative vesicles
chronic- dry, scaly patches, erythema, lichenification, altered pigmentation
NB- most common on face and extensor aspects in new-borns, flexor aspects in adults
Management of eczema
Conservative- avoid exacerbating agents, emollients, soap substitute
Medical- topical steroids, oral antihistamines, ABX if secondary infection
NB- phototherapy, immunosuppressants, biologics for severe/non-responsive cases
NB- can get secondary bacterial infection, eczema herpeticum, and molluscum contagiosum
Management of psoriasis
- Primary care- regular emollients, topical corticosteroid (betamethasone) and vitamin D analogue (Calcipotriol) separate (or (Dovobet- combined)), short acting dithranol
- Secondary care- phototherapy
- Systemic therapy- oral methotrexate, biologics eg. infliximab, etanercept
NB- complication: erythroderma
NB- if corticosteroid doesn’t work, then continue vitamin D analogue (can’t use steroids long-term)
NB- vitamin D analogue (Calcipotriol) is the only one that can be used long-term (wouldn’t use steroids long-term)
NB- need to know the order of steroid potency eg. eumovate, dermovate etc.
Hand foot and mouth disease
Hand, foot and mouth disease is caused by the coxsackie A virus (or enterovirus). Incubation is usually 3 – 5 days.
viral upper respiratory tract symptoms such as tiredness, sore throat, dry cough and raised temperature
small mouth ulcers appear, followed by blistering red spots across the body (most notable on the hands, feet and around the mouth)
Painful mouth ulcers
rash may be itchy
No treatment
Nappy rash
Contact dermatitis
Management of nappy rash
Switching to highly absorbent nappies (disposable gel matrix nappies)
Change the nappy and clean the skin as soon as possible after wetting or soiling
Use water or gentle alcohol free products for cleaning the nappy area
Ensure the nappy area is dry before replacing the nappy
Maximise time not wearing a nappy
Infection with candida or bacteria warrants treatment with an anti-fungal cream (clotrimazole or miconazole) or antibiotic (fusidic acid cream or oral flucloxacillin).
Causes of non-blanching rashes in children
Meningococcal septicaemia
Henoch-Schonlein purpura (HSP)
Idiopathic thrombocytopenic purpura (ITP)
Acute leukaemias:
Haemolytic uraemic syndrome (HUS)
Mechanical
Traumatic (NAI)
Viral illness
Investigations for non-blanching rash
Full blood count:
Urea and electrolytes:
C-reactive protein (CRP):
Erythrocyte sedimentation rate (ESR):
Coagulation screen, including PT, APTT, INR and fibrinogen
Blood culture:
Meningococcal PCR:
Lumbar puncture:
Blood pressure:
Urine dipstick:
Staphylococcal scolded skin syndrome (SSSS)
a condition caused by a type of staphylococcus aureus bacteria that produces epidermolytic toxins
Features;
generalised patches of erythema
skin looks thin and wrinkled
formation of fluid filled blisters called bullae, which burst and leave very sore, erythematous skin
This has a similar appearance to a burn or scald
Nikolsky sign
fever, irritability, lethargy and dehydration. If untreated it can lead to sepsis and potentially death.
Management- IV fluids and ABX
Difference between bullous pemphigoid (BP) and pemphigus vulgaris (PV)
BP- no mucosal (oral) involvement
PV- mucosal (oral) involvement
Causes of hair loss
Alopecia
Tinea capitis
Psoriasis
Discoid lupus
Multiple courses of topical steroids
Aim for a 4 week break before considering another course of topical steroids
Strawberry naevus (capillary haemangiomas)
Not present from birth
Develop rapidly in first weeks of life
If treatment is required (e.g. Visual field obstruction) then propranolol is increasingly replacing systemic steroids as the treatment of choice. Topical beta-blockers such as timolol are also sometimes used.
NB- Cavernous haemangioma is a deep capillary haemangioma
Potential complications
-mechanical e.g. Obstructing visual fields or airway
-bleeding
-ulceration
-thrombocytopaenia
Port wine stain
Unlike salmon patches and strawberry naevus they do not spontaneously regress
salmon Patches
They are pink and blotchy, and commonly found on the forehead, eyelids and nape of the neck. They usually fade over a few months, though marks on the neck may persist.
Bullous pemphigoid vs pemphigus vulgaris
BP- older, no mucosal involvement, Nikolskys negative, tense and firm blisters
PV- younger, mucosal involvement, Nikolskys positive, flaccid/ruptured blisters
Ototoxicity
Ototoxicity is an important side effect of the aminoglycoside antibiotics, which include gentamicin, neomycin, and tobramycin. Neomycin is the aminoglycoside that is most ototoxic.
